SEAWARD
ELECTRONICS
INC.
DC-to-DC Converter
Control Circuit
S E3 4 0 6 3
CIRCUIT
8
S Q
R
7
0.33
6
Vin=25V
100u
CT
Oscillator
Comparator
+
-
5
1.25V
Reference
Regulator
Ipk
2
IN5819
3
CT
470pF
L
220uH
1
4
Vout
1.0uH
100u
Vout
R1 1.2K
R2 3.6K
470u
Co
5V/500mA
(Optional Filter)
Voltage Inverting Converter
Parameter
Line Regulation
Load Regulation
Output Ripple
Efficiency
Short Circuit Current
Output Ripple with Optional Filter
CIRCUIT
Test Conditions
Vin=4.5V to 6.0V, Io=100mA
Vin=5V, Io=10mA to 100mA
Vin=5V, Io=100mA
Vin=5V, Io=100mA
Vin=5V, R
L
=0.1Ω
Vin=5V, Io=100mA
Type
3.0±0.012%
0.022±0.09%
500
62.2%
0.91
70
Unit
mV
mV
mVp-p
-
A
mVp-p
8
S Q
R
7
0.24
6
Vin=4.5V~6V
100u
CT
Oscillator
Comparator
+
-
5
1.25V
Reference
Regulator
Ipk
1
2
88uH
3
CT
1500pF
IN5819
L
4
Vout
1.0uH
100u
Vout
R1 8.2K
R2 953
1000u
Co
-12V/100mA
(Optional Filter)
Preliminary and all contents are subject to change without prior notice.
©2001SEAWARD ELECTRONICS INC.
Tel: 0086-(010)82895705, 82895706
Room1605, Building1, International Pioneering Park, No.1 Shangdi XinXi Road, Haidian District, Beijing 100085, China
http://
www.seawardinc.com.cn
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SEAWARD [ Seaward Electronics Inc. ]
